Q: I’m among the masses who use “going to” and “will” interchangeably. I didn’t think much about it until a friend from China asked me for help on her ESL homework. What is the difference between these two usages?
A: The most common way of expressing a future action is by using “will” plus an infinitive (“I will study tomorrow”).
But there’s another way: “be going” plus an infinitive (“I am going to study tomorrow”).
This second method, the Oxford English Dictionary says, has been in use in one sense or another since the 1400s.
At first, according to the OED, it meant on the way to, preparing to, or tending to, but it’s now used as a more colloquial way of “expressing immediate or near futurity.”
Both methods are perfectly legitimate, though there are subtle and not-so-subtle differences between them.
The most obvious is that “will” is followed by a bare infinitive (like “study”) while “be going” is followed by “to” plus the infinitive.
Another obvious difference is that “will” stays the same through all conjugations (“I will … he will … they will study”), while “be going” does not (“I am going… he is going … they are going to study”).
The Cambridge Grammar of the English Language goes into considerable detail about “will” versus “be going.”
We’ll try to summarize, using our own examples (with apologies to the authors, Rodney Huddleston and Geoffrey K. Pullum).
(1) As far as style goes, “be going” is “relatively informal,” while “will” is neutral. So “I’m going to call her” may sound more casual than “I will call her.”
(2) A wider variety of expression is possible with “be going” than with “will.” For example, “I may be going to study,” or (casting the future into the past) “I was going to study,” “I had been going to study,” and so on.
(3) There’s often more immediacy with “be going” than with “will.” A sentence like “You’re going to fall!” implies NOW! It conveys more urgency than “You will fall!”
(4) Sometimes “be going” implies a simple intention (“He’s not going to come”) while “will” implies willingness or volition (“He won’t come”).
There’s another question hidden in this discussion. We can express future time in English, but do we really have a future “tense” in the strict sense of the word?
Grammarians have traditionally viewed “will” as the sign of the future tense in English.
But modern academic grammarians take another view. They believe that technically English has no future tense, only present and past.
These grammarians say the word “will” in a future construction is an auxiliary verb in the same category as “can,” “may,” “must,” and others.
Future actions, they say, are expressed by tweaking the infinitive or some form of the present tense with an auxiliary (“He will leave”), or with “be going” (“He is going to leave”), or with an adverb or adverbial phrase (“He leaves tomorrow,” “He’s leaving at 4”).
And sometimes, no tweaking is necessary. A sentence like “If he goes, I go” implies future action but uses only present-tense verbs.
Here’s what scholars of grammar are saying today about tense and future time.
In the Cambridge Grammar, Huddleston and Pullum write, “While there are numerous ways of indicating future time, there is no grammatical category that can be properly analysed as a future tense.”
In The Oxford English Grammar, Sidney Greenbaum writes, “Strictly speaking, English has only two tenses of the verb—present and past—if tense is defined as being shown by a verb inflection.”
Future time, Greenbaum says, is most commonly expressed in a verb phrase with “will” or “be going.”
These grammarians have a point. Clearly, if English had a true future tense, we wouldn’t need the auxiliary “will” to express it.
A verb (“know” for example) would have a future form with the inflection built in, so we could say (in effect) “I will know” with a single verb, like speakers of Spanish, Italian, and French.
The Spanish, for example, say it with sabré, the Italians with saprò, and the French with saurai.
But for most of us, the question whether English has a true future tense or merely has other means of expressing future action is largely academic.
The language hasn’t changed, only perhaps our way of looking at it.
For the sake of convenience and readability, here at The Grammarphobia Blog we’ll continue to describe “will” verb phrases as examples of the future tense.
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